1. Field of the Invention
The present invention relates to a display device that can be installed in a vehicle for displaying images to a passenger inside the vehicle. The display device of the present invention can also be utilized as a portable-type display device.
2. Background Information
Regarding display devices that display images for a viewer, there are known technologies for preventing the viewer from experiencing a discomfort or incongruous feeling when the viewer moves with respect to a display section of the display device. This discomfort or incongruous feeling is often caused because the visual information the viewer obtains when watching an imaged displayed on the display section does not match the information from the vestibular organs (semicircular canals and otolith organs).
One example of a display device is disclosed in Japanese Laid-Open Patent Publication No. 10-73785 which discloses using a Fresnel lens or other optical element arranged between the display device and the viewer. The Fresnel lens causes the viewer to see a virtual image projected to a position close to infinity. When the viewer views from below a normal line of the Fresnel lens, the projected image is seen above the normal line. When the viewer views from above a normal line, the projected image is seen below the normal line.
Another example of a display device is disclosed in Japanese Laid-Open Patent Publication No. 8-220470 which discloses mounting the display device a viewer's head. This display device causes an image to appear stationary to the viewer wearing the display device by scrolling the displayed image oppositely to the movement of the viewer's head when the viewer's head moves.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved display device that substantially prevents the viewer from experiencing a discomfort or incongruous feeling when the viewer moves with respect to a display section of the display device. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.